Early operable breast cancer in elderly women treated with an aromatase inhibitor letrozole as sole therapy

BACKGROUND: Primary endocrine therapy (PET) with aromatase inhibitors (AIs) is an option in elderly patients unfit for or unwilling to undergo surgery. We studied the outcome of patients treated with letrozole as PET. METHODS: Patients with early oestrogen receptor (ER)/progesterone receptor (PR)-positive breast cancer treated with letrozole from February 2001 to September 2009 were reviewed. Inoperable and locally advanced tumours were excluded. Reasons for offering PET, response, survival, cause of death, time to initial and best response, fracture incidence, and late failure rates were studied. RESULTS: In all, 104 patients received PET due to frailty (n = 48), comorbidity (n = 30), old age (n = 9), and patient preference (n = 17). Median follow-up was 56 months (4-106). Eighty-five cancers responded to letrozole (stable disease (SD, n = 19), reduction in size (PR, n = 42), and complete response ((CR), n = 24)). Median survival was 51 months (4-103), time to initial response (PR/CR) 4.5 months (2-24), and time to best response 8.5 months (3-50). Letrozole was stopped in 25 patients due to progressive disease (n = 19), side effects (n = 5), and patient choice (n = 1). Only 12 of 49 deaths were from breast cancer. CONCLUSION: Letrozole is a reasonable alternative in elderly women with early ER/PR-positive invasive breast cancer who are unfit or unwilling to undergo standard therapy. British Journal of Cancer (2011) 105, 1825-1829. doi: 10.1038/bjc.2011.470 www.bjcancer.com Published online 8 November 2011 (C) 2011 Cancer Research UK